The present invention relates to apparatus for transporting articles to a series of workstations and for raising and lowering the articles into and out of the individual workstations. This apparatus includes at least one belt conveyor which moves the articles past a series of workstations and means for moving the articles into and out of the workstations, as well as means for controlling these operations. The apparatus of the invention is useful for operations performed upon ultrasonic and/or processing units, and the apparatus may include stations for performing various functions on the articles, including stations at which the articles are dipped into vats or containers of appropriate processing liquids or materials and may also include drawing stations.
One existing article transport apparatus includes transport units that move along tracks that are above and/or behind the apparatus. For conveying the articles along the tracks, the apparatus may include article transport means such as a basket. Further, the apparatus may be fitted with a lifting mechanism associated with the basket for raising and lowering the articles to be operated upon. The articles to be operated upon are transported to a number of stations in sequence for respective treatments to be performed. The articles are then inserted into the individual stations for the respective treatments and are withdrawn from the stations to be transported to the next stations for further processing.
In another known article transport apparatus, the baskets for transporting the articles are fed or transported from workstation to workstation over a roller track using a single lifting girder device.
Known transport apparatus sometimes have the disadvantage that they require too much space. Because the transport apparatus may pass over or above the individual work stations, requirements for cleanliness of the articles being operated upon and/or of the workstations, which may include open-top vats, often cannot be satisfied. Therefore, setting up such equipment under clean room conditions may be accomplished only at great expense. Furthermore, in some known apparatus, the transportation means must be changed or transferred during conveyance. This may knock or bang the articles being transported and their transport carriers, which is undesirable, especially with precision goods as in precision optics supplies.